VIEWS: 2 PAGES: 21 CATEGORY: Chemistry POSTED ON: 9/4/2010
This invention relates to a method for manufacturing an electrically conductive electrode for use in batteries. The invention also relates to the application of said electrode as the cathode in a primary alkaline battery.BACKGROUND OF THE INVENTIONPrimary alkaline electrochemical cells typically include a zinc anode active material, an alkaline electrolyte, a manganese dioxide cathode active material, and an electrolyte permeable separator film, typically of cellulosic and syntheticfibers. The anode active material can include for example, zinc particles admixed with conventional gelling agents, such as sodium carboxymethyl cellulose or the sodium salt of an acrylic acid copolymer, and an electrolyte. The gelling agent serves tosuspend the zinc particles and to maintain them in contact with one another. Typically, a conductive metal nail inserted into the anode active material serves as the anode current collector. The electrolyte can be an aqueous solution of an alkali metalhydroxide for example, potassium hydroxide, sodium hydroxide or lithium hydroxide. The cathode typically includes manganese dioxide as the electrochemically active material admixed with an electrically conductive additive to enhance electricalconductivity, an optional polymeric binder, and other optional additives, such as titanium-containing compounds including anatase-type titanium dioxide and other alkaline earth metal titanates. Because manganese dioxide typically exhibits relatively lowelectrical conductivity, an electrically conductive additive is needed to improve the electrical conductivity between individual manganese dioxide particles and also between the manganese dioxide particles and the steel container that encloses the cellcomponents and that also serves as cathode current collector. Suitable electrically conductive additives can include, for example, conductive carbon powders, such as carbon blacks, including acetylene blacks, natural graphites, synthetic graphites,includ
"Battery Cathode And Method Of Manufacture Therefor - Patent 6620550"